MONDAY, Jan. 25 (HealthDay News) Researchers say they've spotted a new genetic risk factor for Parkinson's disease, as well as a link between the illness and two other factors, metabolism and vitamin B6.

"Our study reveals the interaction of genetic and environmental factors such as dietary habits in the pathogenesis of Parkinson's disease," Dr. Matthias Elstner of Germany's Ludwig-Maximilians-Universitat Munich, said in a news release from the German Research Center for Environmental Health.

Elstner is lead author of a new study published in the January issue of the journal Annals of Neurology.

The researchers studied neurons to understand how genes change their activity due to Parkinson's disease. They found a gene that seemed important and looked for it in 1,200 Parkinson's patients and 2,800 healthy people. It was discovered that a gene variant boosted the risk of the disease.

According to the study authors, the gene variant may affect the activity of an enzyme in the brain, called pyridoxal kinase (PDXK). The role of PDXK is to convert vitamin B6 from dietary sources into an active form that is required for the production of dopamine, a neurotransmitter that has long been known to be associated with Parkinson's disease.

"Although this variant is responsible for only a slight contribution to the overall risk for Parkinson's disease, our findings could aid in developing individualized therapies," Elstner said.